Why do credit scores differ?

There are three major credit-reporting bureaus—Equifax, Experian and Transunion—and two scoring models—FICO or VantageScore—that determine credit scores. Financial institutions use different bureaus, as well as their own scoring models. Over 200 factors of a credit report may be taken into account when calculating a score and each model may weigh credit factors differently, so no scoring model is completely identical. No matter what credit bureau or credit scoring model is used, consumers do fall into specific credit ranges: Excellent 781–850, Good 661-780, Fair 601-660,
Unfavorable 501-600, Bad Below 500.